1. Field of the Invention
The present invention relates to cranes or the like and more particularly relates to heavy lift cranes having interconnected boom supported and propelling units and being capable of lifting and carrying 600 tons or more while requiring a minimum of power.
2. Description of the Prior Art
Cranes or the like having interconnected boom supporting and propelling units are disclosed in U.S. Pat. Nos.: McL Cameron 2,452,662; Lampson 3,836,010; Greenlay et al 3,868,022. German Pat. Nos. 1,180,502 and 1,246,969; and Netherlands Pat. No. 64/5689 also disclose similar types of cranes. However, the complexities and large number of moving parts in the prior art cranes, as compared to the crane of the present invention, are costly, require frequent and costly maintenance, and also require more power during operation than is required by the crane.